1. Classwork Answers— Polyatomic Formulas  K 2 SO 4 8) Cr(NO 3 ) 3  NO 2 9) IO 2  SBr 4 10) Mg(OH) 2  Mg 3 (PO 4 ) 2 11) Hg(OH) 2  Na 2 SO 4 12) Na 3 PO 4  PCl 5 13) N 2 O 5  SeCl 3 14) CH 4 15) Ca(NO 3 ) 2

2. Can we go in reverse?

3. Binary Compounds: Chemical Nomenclature 1) Write an element’s oxidation number over the element symbol. 2) Cation, Anion—write the element name 3) Add the ending -IDE to the second element/anion

4. Example 1: LiCl

5. Example 2: Al 2 S 3

6. Try…… 1) MgO 2) CaBr 2

7. Transition Elements 4) Place a Roman numeral matching the charge/oxidation # on an element after the positive element’s name. Roman numeral is put in () (ex. (II)). Roman numeral indicates the oxidation number on an element can vary. -Go back to Step #3

8. Example 1: CuS

9. Example 2: CoBr 2

10. You Try….  SnO  CrCl 3

11. 5) If both elements are found on the RIGHT side of the periodic table, use the appropriate prefix for a given element. -Go back to Step #3

12. Example 1: CO 2

13. Example 2: CCl 4

14. You Try…. 1) SO 2 2) SBr 3

15. Compounds with Polyatomic Ions: Chemical Nomenclature 1) Write oxidation # for each element/polyatomic ion in the formula 2) Write the element and/or polyatomic ion names. 3) If a transition element (an element where the oxidation # varies), use a Roman numeral to indicate an element’s oxidation # in the chemical name. *NO –IDE ENDING!!!!

16. Example 1: ZnCO 3

17. Example 2: CuSO 4

18. You Try……  Mg(CN) 2 2) Sr(NO 3 ) 2

19. Classwork: 1) Ni 3 (PO 4 ) 2 6) Mg 3 N 2 2) AgBr7) BiI 3 3) SnCl 4 8) (NH 4 ) 2 SO 4 4) (NH 4 ) 2 S 9) ZnCO 3 5) HgF 2 10) Cu 2 S